1. Field of the Invention
The disclosure relates generally to power management methods and systems, and, more particularly to methods and systems that dynamically adjust a working clock of a media processor according to a running cycle required for executing a data unit.
2. Description of the Related Art
With growing demands for performance, quality and functionality, designs for processors such as media processors have increasingly become large and complicated, with function thereon easily failing due to deficiency of power design. Consequently, improvement of power consumption efficiency has become a key factor in processor design.
Power management is very important in media systems. FIG. 1 illustrates a conventional media system 100, comprising a main processor 110, a media processor 120, a memory 130, an input/output unit 140 and a display unit 150. The media processor 120 performs related video operations, such as encoding and decoding, 2D and 3D animation, MP3 decoding, and others. To smoothly play back video via the input/output unit 140 and the display unit 150, the media processor 120 must prepare sufficient video signals. The media processor 120 performs a large number of tasks at some times, and few tasks other times. The imbalance is due to the performance requirements of the media system 100, such as frame rate maintenance and image complexity. Power consumption relates to working voltage and frequency supplied to the media processor 120. If voltage and frequency are higher, the media processor 120 consumes more power. Conversely, if voltage and frequency are lower, the media processor 120 consumes less power.
In conventional power management, the main processor 110 monitors conditions such as system temperature and/or remaining battery power of the media system 100 to adjust working voltage and frequency accordingly, and supplies the adjusted working voltage and frequency to the media processor 120 for power management. Further, due to the operational imbalance described, power requirements differ for respective periods. Since the main processor 110 must expend resources to periodically monitor media system 100, including the overall function of the media processor 120 for related adjustments, the main processor 110 may be overloaded.
Additionally, conventional power management cannot perform related power adjustment and management for the difference between execution situation and performance requirement, resulting in instability of power consumption when media processor 120 is processing video data. In some situations, sudden high current in some periods may generate unexpected calorific capacity, damaging and shortening the life cycle of the media system 100.